Ferroelectric switching of chiral discotic lyomesophases

By diluting a ferroelectric columnar liquid crystal with dodecane as apolar organic solvent, soft columnar phases as well as the chiral columnar nematic phase (N-C*) were achieved as lyomesomorphic systems. All obtained lyomesophases exhibited polar switching over a wide temperature range, even down to room temperature. We found an unusual concentration dependence for the selective reflection observed in the highly twisted lyotropic columnar nematic phase. Different possible models are proposed which could explain the observed optical and electro-optical properties of the studied lyomesophases.